Iem1

Morning guys,

Just after some advice on how others go about image acquisition. I am new to nightscapes, only been out a few times recently under the stars with my 14mm Samyang lens and my astro modded 600D and my Sky Guider pro.

I am interested to learn how others go about image acquisition, the techniques used/ISO settings/exposure times/Total integration times and the like. Just looking for ways to improve on my own methods.

I currently use ISO 1600 as a staple and 90 second exposures with my 600D, here is my latest capture. 

this is x4 90 second exposures at ISO 1600 of both the foreground and sky, the sky being stacked in sequator, taken on a moonless night in a bortle 3-4

I notice the image is quite light, and the milkyway a little dim. I am thinking next time I might try dropping to ISO 800 and perhaps increasing exposure length? Not sure how else to approach it. Is x4 90 second subs considered a decent total integration, or extremely short (as with Deep Sky imaging)?

I am using the technique of imaging the foreground first (Usually while waiting on clouds to clear) and then for the sky I will angle the camera upwards a bit, lowering the foreground in the FOV in order to make blending the images easier (I like to keep a more natural effect with the gradient of the horizon in shot). Did not work 100% here as there is some overlap present near the mountains, I must have shifted left or right while waiting for clouds to clear.

Any advice/tips on things to try or how to improve is appreciated, cheers guys!

Thank you Wimvb for the info mate

But tonight did not go to plan!  

I forgot a screw that attached my RDF to my scope, a single screw which put a halt to the deep sky imaging session! I did not fancy trying to find anything by eye without the RDF.

Luckily though I did pack my Samyang 14mm! So between clouds I grabbed a few shots, stacked them and (very) crudely blended the separate foreground/background in PS. It is not particularly good, but at least I did not leave empty handed  

1 hour ago, ONIKKINEN said:

Longer subs will have more signal to noise ratio so noise is less apparent. With DSLRs the read noise of a single frame can be quite significant and is always the same, regardless of exposure time. So if read noise is the same between shots but one has 2x the time compared to the other it must have better SNR. But also, the cygnus wall is a busy target with detail everywhere, so it might just be that walking noise is less apparent because you stretched the image less. Hard to say, because of the difference in resolutions.

Speaking of resolution, binning is also an effective way to reduce noise. Try resampling your triangulum to 50% resolution, it will wipe out a lot of the noise.

Thank you for the info mate.

I might test 60 seconds, see how I fare with them. The longer the better. Want to get as clean of an image as possible.

Will look into resampling too!

1 hour ago, Grant93 said:

I wouldn't try to answer that last question as I am a newbie to this myself, I have had pictures where walking noise is far more evident than others, for no known reason to myself. I'm just commenting to say these are some nice images!

What do you use to process? Can't wait to see your m33 😀

Grant

The first Triangulam image was done in Photoshop, soft stretches and colour balance. Then I use starnet to remove the stars and do a harder stretch and saturation if I remember correctly.

I believe this was the final Triangulum image I ended up with after I tried to heal the image with a mix of SiRiL and PS work (Removing banding and trying to remove the light leak)

Not sure how it comes out posted here as I am uploading from my phone

17 minutes ago, Grant93 said:

Nice picture!

I also own a SGP, and I also did this once with a 600d and SMYG 135mm Lens, with 10 seconds between exposures. I also only did it every 4-5 frames, and probably every 15 frames I would fiddle with the DEC bracket a bit (slightly loosen one side and tighten the other), so you're not only dithering in RA but DEC also. You will find the 10 or 15 seconds between frames eats up your imaging time massively, when you've been sitting out for 4 hours but got 3 hours 15mins of data (but very worth it if you're willing to do it).

However, in this weather I cannot be doing with sitting out there for hours on end haha (unless I'm out with the binos or dob🤓). I would rather set up, spend 15 minutes making sure its running ok, then go and sit inside where I can see the rig running on my backgarden from the patio door, whilst watching TV 😅. But the sad thing is, when you have done it once, and you see the difference, it means more money to be spent on a mini PC and guiding set up to be able to automatically dither 🥶 Which I am planning on making before christmas 😅.

But to answer your question: Yes 15 seconds should be plenty 😃.

Good luck & wrap up warm

Grant

Yes! It is demoralizing how much imaging time is lost due to rest bewteen shots and to make matters worse, I used to take dark frames too. So another 30-40 minutes would be lost taking those. Thankfully I do not bother with those now  I just use Bias & Flat.

I have my thermals ready for tonight, it is going to be very cold indeed. Hoping my little USB Dew heater manages, it doesn't get particularly warm so I am not sure it will! That and DSLR batteries die remarkably quick when it is sub 5 out!  

13 minutes ago, ONIKKINEN said:

For it to be effective you want to dither in both axis, so move RA and DEC a bit. It will make a big difference to your noise levels.

 

Another way i dithered with a DSLR was to tilt the camera 90 degrees every now and then. Only works with small targets that can be cropped though. Not sure how you would do this with the SGP though.

Thank you ONI, I shall try as you and Grant suggested and do both RA & Dec via key pad + tightening/losening screw.

I will for sure have to check PA often if adjusting the DEC. The SGP is very easily knocked out of alignment.

A heck of a lot of extra work, hoping all the effort pays off and I can get a nice image. I do love the Triangulum galaxy  

The walking noise is nowhere near as prominent in my 60 second subs; This around 2 hours of 60 second subs of the Cygnus Wall

Is this reflective of a longer exposure time? are 30 second subs more susceptible to walking noise than 60 second subs? Or might there be something else causing this?

Cheers guys 

Sidenote: The image above was around 2 hours of 30 second subs with no dithering 

Morning guys,

I am going to head out tonight to a bortle 3-4 sky in an effort to tackle the Triangulum galaxy again. Will be my first deep sky outing in a few months as I am back in Uni and have been doing some nightscape instead.

This was attempt one:

I was super pleased with the detail I managed to grab, but as you can see, the walking noise absouletly kills the image! That and a suspected light leak damaged the image.

Anyway, tonight's plan is to try fully manual dithering. I use a Sky guider pro and a WO Z73 with an astro modded 600D, somewhat luckily, the Triangulum galaxy is fairly small in the frame and relatively easy to find/center so I am not too worried about losing it in the frame or shifting it too far between frames, I have a bit of room to spare. I realise an automated system dithers by just a few pixels, think mine will be a touch more than that  

My plan is simple, but arduous. 45 second subs (1 minute is doable, but requires almost perfection, might struggle while dithering too) while dithering by way of simply pushing either the left or right R.A. movement keys on the SGP between frames.

Is it likely that taking the time to do this between frames is going to have an impact? I usually have ~15 seconds between each image, so the rig should have ample time to settle down before the next 45 second shot starts.

Cheers guys, Excited to get back out there!

I tried a few times to get blend it together using different methods and struggled a lot, need more experience in PS I think before I can hope to tackle it.

In the end I gave up and used @fwm891 magnificent work and attempted to add a personal touch to it, hope you don't mind

settled with this;

I quite like the dark and subtle foreground effect...with the added bonus of hiding my mistakes too  I had a proper play around the trees with masks, adjusting Exposure/colour balance trying to make it all click. I am super happy with the result! Second ever nightscape, and, with a little (A LOT) of help from SGL friends, it looks great! Thanks again guys, really appreciate it.

Makes it more rewarding that this was a last ditched effort on the way back after spending 2-3 hours at another location trying to get something to work. 

This was my first attempt at a nightscape;

this was 60 seconds tracked sky and 60 seconds untracked foreground, was much much easier to blend for sure. Nice and flat! 

I was about to post 'Where I had got to' in my progress before fwm posted that amazing effort!

..Think Il keep the monstrosity I had created to myself now  

Thank you guys, il be tinkering with it for most of the day and trying out the suggestions.

Very happy it was able to be salvaged as I was quite pleased with the images for my second attempt at a nightscape!

Thanks again for your time folks  

9 minutes ago, ollypenrice said:

In the end the best I could do, which isn't very good,  was to paste  one onto the other (foreground on top), align them and use the colour select tool to pick the bright sky, after which I erased it.

You have the Coathanger Cluster showing particularly sweetly. One of my favourites!

Nest time, pick a simple foreground!!!

Olly

That is a great effort! Thank you for taking the time to help me out, I do appreciate it  

Il have a few more attempts and see if I can find some guides online, but the movement between the foregrounds is huge for some reason. maybe I nudged the mount or something.

That or I will just cut my losses and take the original sky image as the completed image and just have a slightly blurred silhouette of the church/trees  

29 minutes ago, ollypenrice said:

Hmmm, you've made life hard for yourself by choosing a foreground which has sky both above it and below it! 😜 (Those branches sticking out into the sky on the right hand side.) Without that, you could just paste the foreground image on top of the sky image, and move the foreground up a bit to cover the blur. However, I do have an idea... I'll try it and get back if it works!

🤣lly

Story of my life!  

hmmm, Il have a play with that idea too. Haven't yet tried necessarily moving either of the images, just cutting and dropping and trying to fix...Which I haven't had much success with  

lesson learnt though, nice flat uniform foregrounds that fall within the capabilities of my basic PS abilities lol

Thank you Olly!

17 minutes ago, Alien 13 said:

I think what I would do is slightly enlarge the foreground layer so that it overlaps any motion blur from the image of the sky then blend the two layers together. Then paint out the fiddly bits using a layer mask.

Alan  

Thank you Alan! Im going to give this a shot shortly!

...If all else fails, I did have another plan. I did take a full FOV image of the milkyway near the zenith...that would drop in nice and easily behind he foreground I think...But I would feel like I am cheating doing that..and I do not think it would look very natural  

Hey guys, hope you are well!

I had a second outing with my new Samyang lens last night to try some nightscapes, I am quite happy with how it went overall.

I got what I think is a nice image, 90 second tracked milkyway shot and a few 90 second foreground shots that I have stacked in PS. I am struggling to blend the images unfortunately. Compared to my first attempt, the foreground has moved between foreground/star shots and so it is not as simple as cutting out the 'bad sky' as was the case with my first.

Is it still possible to blend these? I think if I can blend them I will need to use the healing brush to clean up the overlap between leftover bad sky etc But I cant really get that far yet.

Sorry if none of that makes sense, I am new to nightscapes and this method of processing  

Here is a tif of the sky and the stacked foreground if anyone wants a closer look to see if it salvageable. 

Sky(tif).tif

Stacked land (tif).tif

And here is png for initial idea of what I am working with.

And the land;

Any advice is appreciated  

This is my first attempt at landscape imaging;

I think the upload ruins the quality quite a bit, its a pretty sharp and nice image if I do say so myself!  I will attach the tif too.

Nightscape.tif

clouds were forescast, but I could not resist giving it a shot anyway. As luck would have it, The Pleiades poked their head up into frame too!

Because of the clouds, I took a single 60 second exposure of both the foreground and the sky at ISO 1600, though I think the foreground was a little over exposed?

I also realise its at a bit of a tilt. Struggling to get the ball head mount where I wanted it

But all in all I am happy with it, it was fun and it is a pretty image to an untrained eye if nothing else.

Thanks guys for the help!

Any tips

13 minutes ago, Adam1234 said:

The Samyang is a good choice. Here's some images of the Milky Way I recently took with mine

https://stargazerslounge.com/topic/383631-milky-way-in-cornwall/?tab=comments#comment-4148109

I would definitely recommend the ball head. 

@900SLI would also be interested in how to check if the Samyang is de-centered or has optical issues

Some fantastic images there! 

How do you got about taking the foreground? I have seen people use single images aswell as slightly longer exposures on the foreground to clear it up.

I plan on using my SGP for the stars, I understand focusing (basically getting the stars as small as possible) ..But what ISO should I roughly be looking to use for a 600D? ISO 800 is the sweet spot for the camera in deep sky imaging, same principle or is it likely a higher ISO will be needed?

Sorry for the barrage of questions, I'm trying to formulate a workload before I get out there

those images above are the first time I have used a DSLR without a 430mm refractor hanging off the end of it

Cheers 

Here are a few quick shots I took, no tripod etc ..Just to test it out and get used to the settings. I think it seems ok. Although I am noticing a darkening in the bottom corners on some shots. A uniformly lit subject doesn't display it, so not sure if its a defect or just how it is.

Messed around with colour balancing in PS using the camera raw filter.

Lens arrived today

Question about the actual set up, am I correct in thinking I need something like this; https://www.wexphotovideo.com/manfrotto-494-ball-head-1643103/?account=853-353-2386&campaign=&group=&mkwid=_dc&pcrid=541679743651&kword=&match=&plid=&pgrid=126481880357&ptaid=pla-559558469182&si=&gclid=CjwKCAjw49qKBhAoEiwAHQVTo8wn1W8Ejp846VT9fk2-oTUqVKt0Zd9fpn8uXvXDPkgsyZ8eLWlA9hoC3_wQAvD_BwE

which will sit on top of this;

 While holding the Camera setup?

I assumed I could use the circular head pictured above for the camera as a static base, but the thread will not fit the camera. Assuming that will hold the ball head.

Also, how best can I check if my Samyang is de-centered?

Apologies for basic questions, completely new to this setup/lenses

cheers guys. 

Don't worry so much about the image quality, I just find it amazing enough to be looking at another planet and its satellites

no such thing as a bad photo when you stop and think about what you are actually seeing

Aperture is set as its connected to a telescope I think?

That's a good first image! Something to be proud of for sure

I cant comment on guiding and star shape, but as you said, a short integration time on a full moon (near the moon at that) is always going to be tough going with a one shot colour camera. Especially for targets such as pac man (nebulas in general really). A moonless night + much more integration time will be the biggest improvement I think.

Did you take calibration frames? (Flats/Bias). Also must haves!

hopefully someone more technically minded will give advice about the scope/guiding/specific image details shortly.

Awesome stuff! Took the plunge and ordered it

excited to use it with my astro moded 600D and the SGP! Hopefully get some lovely images, back on the coast of Wales (And near Ellan Valley) in Wales, so should be a blast

Thanks again guys 

Good point! Thank you for bringing that to my attention!

Struggling to find anything smaller, but I have found this.

https://www.mpb.com/en-uk/used-equipment/used-photo-and-video/used-lenses/used-canon-fit-lenses/samyang-14mm-f-2-8-ed-as-if-umc-canon-ef-fit/sku-1296143/

Seems like a better option?

Thanks

Thank you for the advice guys!

Am I correct in thinking something like one of these would be a decent option for my Canon 600D?

https://www.wexphotovideo.com/canon-ef-20mm-f2-8-usm-lens-used-3014427/

https://www.wexphotovideo.com/canon-ef-28mm-f1-8-usm-lens-used-3016228/

I have no experience with photography (outside of my first summer tinkering with deep sky imaging) so I could be wildly wrong  

Hi guys,

Im sure this has been asked a million times, but I am looking to try my hand at some landscape astrophotography and I am wondering which lens would be best suited to my equipment.

I currently do deep sky imaging with a WO Z73, skyguider pro and an astro modded Canon 600D, so planning on using the SGP and 600D for landscape too

I have a budget of around £200-£300, so not looking for anything fancy.

I will do more independent research, but if there is one thing I have learned during my astro journey its the advice from the people who have been there and done that is absolutely invaluable and will often save you a lot of money and time  

I am assuming calibration frames (Bias/Flats) are required and acquired in the same manor as with Deep sky imaging? 

Any recommendations on a lens are most welcome, I am based in the UK if that helps. Planning a trip to Currys/PC World later to go take a gander at what they have, but would love to look for something specific after being advised here.

Cheers guys!  

I have the same scope and had exactly the same problem (but with a 600D :D) 

A red dot finder is an absolute must have for our setups, its like night and day when trying to find something.

This is what I got; https://www.firstlightoptics.com/finders/baader-30mm-sky-surfer-iii.html

attach it to the scope, keep it as straight as possible by eye, whereever it's pointing should be roughly already in your field of view (of your scope) ..Then you can find a bright star using it, check live view and you should see it there too. Calibrate the red dot finder appropriately and away you go. (If the moons out, even better, use that)

I could barely get Andromeda in my FOV without it, but with it, Andromeda, NA nebula, Pacman nebula, Triangulam galaxy, cygnus wall, whirlpool galaxy etc etc are all quite straight forward to find and frame now even without go to

hope this helps.

I was around 21 - 22 and working in an opticians in London (around 3-4 years ago). I was bored one day and went into a WHSmiths and was looking for a book to read. I don't often read in all honesty, but on the rare occasions when I do, I usually prefer something factual. I found 'The Human Universe' by Proffesor Brian Cox and Andrew Cohen, later learning (after reading it) that it accompanied a popular TV series too. The book primarily covers topics related to profound questions about the Universe and how we came to understand our place in it.

This book sparked my interest in Astronomy and Science, where there was previously none. From there I went to college to do an access course in science, I dont really have GCSE's, nevermind A-Levels as I mucked around in high-school. I did that access course two days a week whilst working in the opticians the other 5 days a week to pay the rent, attending GCSE Maths and English in the evenings after my actual access to science lessons during the day (Those were long days! Out at 7 am, back at 10 pm!).

After around 4 months or so, and after completing a good few assignments in Maths/Chemistry/Biology/Physics modules at merit/distinction level I was feeling pretty burnt out of the 7 day weeks. I contacted a University enquiring about whether or not I had done enough to earn a place to study with them, and was told to apply and basically keep your fingers crossed! I assumed it was subject to space and availability as technically speaking I still had absolutely no real qualifications.

I am now going into my final year of studying Astrophysics at University, and hopefully obtaining my degree in less than a year from now! During my time at University me and a few friends have often borrowed the telescope from the lab in Uni (Newtonians and the like mostly, they won't let us near the big one up on the roof just yet.. :D) for basic visual and imaging the Sun.

This year I was finally in a position to purchase my first Astrophotography setup. I bought a mobile and lightweight setup owing to travelling around a lot, back and forth Uni and dark sky sites. So I am just learning the basics of the trade with my William Optics Z73, a SGP and an Astro Modded Canon 600D. And thanks to the guidance from SGL members, I have loved every second under the stars with my first AP setup and feel I am able to do basic processing now 

I have future plans to upgrade the mount and establish a guiding system as I now feel comfortable with my current setup, I think I would be ok with adding another layer of complexity. I can't wait for that!

Big thank you to the folks here at SGL, your advice has been invaluable

Also, I read the 600D has a sweet spot of ISO 800. Perhaps it performs a little bit different when unmodded, but I only use 1600 with 30 second subs to find targets, then straight back to ISO 800 when imaging. I find 1600 tends to wash out my images a bit too much, even under dark skies.

Looking good!

Have you thought about getting the 600D astro modded? I also use a 600D at the moment and the astro mod (Mine has had one of the IR filters removed I believe) makes a massive difference when imaging rich Ha nebula like the NA nebula. Well worth the investment if you're going to stick with the 600D for any length of time.

Bizzarely, I think I actually imaged the same two targets with the same camera on the same night